1. Field of the Invention
This invention relates to a disk drive suspension comprising a microactuator element of, for example, lead zirconate titanate (PZT).
2. Description of the Related Art
A hard disk drive (HDD) is used in an information processing apparatus, such as a personal computer. The HDD comprises a magnetic disk rotatable about a spindle, a carriage turnable about a pivot, etc. The carriage, which comprises an actuator arm, is configured to be turned transversely relative to tracks of the disk about the pivot by a positioning motor, such as a voice coil motor.
A suspension is mounted on the actuator arm. The suspension comprises a load beam and flexure superposed thereon. A slider, which constitutes a magnetic head, is mounted on a gimbal portion formed near the distal end of the flexure. The slider is provided with elements (transducers) for accessing data, that is, for reading or writing data. The load beam, flexure, slider, etc., constitute a head gimbal assembly.
In order to overcome the increase in the recording density of disks, the magnetic head should be more precisely positioned relative to the recording surface of each disk. To attain this, dual-stage-actuator (DSA) suspensions have been developed that combine a positioning motor (voice coil motor) and microactuator element made of a piezoelectric material, such as lead zirconate titanate (PZT).
The distal end of the suspension can be quickly moved by an infinitesimal distance in a sway direction (or transversely relative to tracks) by applying a voltage to and thereby deforming the actuator element. As disclosed in Jpn. Pat. Appln. KOKAI Publications Nos. 2010-146631 (Patent Document 1) and 2010-218626 (Patent Document 2), moreover, there are known DSA suspensions in which a microactuator element is disposed on a gimbal portion of a flexure.
In a head gimbal assembly in which a slider and microactuator element are disposed on a gimbal portion, a tongue is formed such that the slider is mounted thereon. This tongue abuts a supporting protrusion (e.g., a convex surface of a dimple) formed on, for example, a load beam. The tongue is swingably supported on the load beam by the supporting protrusion. The tongue may sometimes strongly vibrate if the suspension is subjected to external mechanical shock or the like. Further, the tongue may separate from the dimple (dimple separation). To prevent such trouble, a limiter member is conventionally provided between the tongue and a supporting member, as disclosed in Patent Documents 1 and 2, for example.
The limiter member can effectively prevent vibration of the tongue if it is provided in a position where the tongue vibrates strongly. If the limiter member is connected in such a position, the junction between the tongue and limiter member may possibly be peeled off by stress repeatedly applied thereto.